The statements in this section merely provide background information related to the present invention and may not necessarily constitute prior art.
In many actuators which are used in connection with a driving dynamics regulation of a motor vehicle, actuation movements have to be carried out precisely to achieve a respective desired effect advantageously influencing the handling of the vehicle. A very high absolute precision and resolution of the position sensor system is required with respect to the position regulation and position monitoring of an active rear axle steering, for example, to generate the suitable reaction of the rear axle steering in dependence of a steering wheel position.
Sensors which are able to determine the position of an element of the actuator sufficiently accurately over its total excursion range are frequently expensive. Optical sensors admittedly deliver the required accuracy; however, they become dirty easily and are therefore not sufficiently reliable.
A further aspect which has to be taken into account in the conception of a rear axle steering actuator relates to the calibration of the position determination system. Since every actuator and its sensors have individual tolerances, every actuator or its position determination system has to be calibrated. The determined calibration data must be provided to a control device associated with the actuator in a suitable manner, with a first installation or a replacement of the actuator being possible without interfering with the control device.